Abstract: An intelligent light emitting diode lamp tube compatible to a T5/T8 electronic ballast comprises a tube body, a circuit board provided with at least one LED lamp string to be disposed in the tube body, an integrated circuit disposed on the circuit board, a selection circuit comprising a first conduction loop and a second conduction loop configured with an inductor, and a switch member connected to the integrated circuit. When the intelligent light emitting diode lamp tube is connected to a self-oscillating electronic ballast or an IC-controlled electronic ballast, the internal arithmetic of the integrated circuit can be utilized to conduct the selection circuit and the switch member to change resonance frequency of electrical circuit, so that effects of low power consumption, high adaptiveness and energy conservation can be attained.